1. Home
  2. Electronics Down Under
  3. Transformer testing

Transformer testing

I have in 50 ac tranny@ 40 amps , it's unmarked but is 240 primary however how to id windings , any suggestions as of course I wont be just plugging stuff in , ex telecomms

--
X-No-Archive: Yes
Reply to
atec77
Loading thread data ...

Well the dc resistance of the primary would be much higher than the secondary for starters. If there are taps on the primary it should be easy to identify the highest resistance pair to start off with and experiment with since if it's 415v you wont be doing any harm by hooking that up to 230v.

Reply to
Rheilly Phoull

"Rheilly Phoull"

** For a 230 VAC primary - expect 0.5 ohms

For the 50VAC secondary - expect 22 milliohms

A "soft start" circuit will be needed for sure - or it will trip the breaker as soon as you switch it on.

..... Phil

Reply to
Phil Allison

Like you say :-) What do you reckon to a 30R 100W with a switch across it ??

Reply to
Rheilly Phoull

** Depends if the PSU has to come up while under load or not.

If it does, then a couple of chunky 15 amp rated, 2 ohm NTC thermistors are the go.

.... Phil

Reply to
Phil Allison

I took a quick measurement and then excited the secondary with 10 v ac , soon worked out the correct primary taps to arrive at the desired 24vac out

--
X-No-Archive: Yes
Reply to
atec77

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.